The present invention relates to a surgical instrument for determining the size and/or height of an intervertebral implant insertable into an intervertebral space between two adjacent vertebral bodies of two vertebrae of a human or animal spinal column, wherein the intervertebral implant comprises a first abutment element for abutment against an articular surface of one of the two adjacent vertebral bodies as well as a second abutment element supported directly or indirectly on the first abutment element for abutment against an articular surface of the other of the two adjacent vertebral bodies, wherein the instrument comprises a holding part defining a longitudinal direction and at least one test implant, which comprises a first and a second test-implant abutment element each having at least one abutment surface for abutment against one of the articular surfaces, wherein provided on a distal end of the holding part is at least one abutment-element holding element for detachable connection to the at least one test implant.
The treatment of degenerative diseases in the region of the spinal column very often involves the surgical removal of intervertebral disk tissue. Adjacent motion segments, i.e. adjacent vertebral bodies, are then fused by means of a bone chip and/or artificial intervertebral implants. An alternative to the fusion of adjacent vertebral bodies is to implant artificial intervertebral disks, by means of which a mobility of adjacent vertebral bodies relative to one another may be at least partially maintained.
An artificial intervertebral disk is used, inter alia, to restore the original intervertebral disk height and re-stabilize the spinal column.
For determining the required size and/or height of the intervertebral implant, various instruments or test implants are known, which are introduced into the cleared intervertebral space to determine the size and height. In dependence upon the size and height of the implant determined by means of the instrument and/or test implant, the actual intervertebral implant is selected and then implanted.
Therefore, it is desirable to improve an instrument of the initially described type in a way that allows the size and/or height of an intervertebral implant to be determined in a simple and different manner.